The towers were designed to survive a plane hit. So what went wrong?
A look at the World Trade Center towers from an engineering perspective. Explanations about why the Twin Towers were constructed the way they were, and how those design choices contributed to their inevitable collapse on 11 September 2001.
Direction
Restrained approach lets the physics speak.
Editing
Brutal clarity in explaining progressive collapse.
Trivia, insights & behind the scenes
The 'stacked pancake' model of collapse was initially controversial—some engineers argued for controlled demolition theories until this documentary's physics simulations gained traction.
Released just two years after 9/11, this was among the first mainstream attempts to replace conspiracy panic with structural engineering literacy—PBS knew Americans needed answers, not more fear.
US
